A current mirror circuit is an elementary circuit in an analog integrated circuit. It may be used for mirroring of currents, or may form a bias circuit to provide bias for other circuit. A cascode current mirror is often adopted due to its large output impedance and high mirroring precision, but a current mirror with a common cascode structure limits an output swing of the current mirror.
In order to realize a wide wing output of the current mirror, the structure of the cascode current mirror can be improved, but the improved structure of the cascode current mirror is likely to increase power consumption, or cannot implement the function of the current mirror.